1. Field
The disclosure relates, generally, to public addressing (PA) systems and methods and, in particular embodiments, to systems and methods in which one or more personal communication devices (PCDs) are operated as a microphone for a PA system. Further embodiments relate to a PCD configured to operate with such systems and methods.
2. Background
PA systems can be used in various contexts, including conferences, meetings, seminars, concerts, and other events or activities, to amplify an audio input, such as a person's voice, a group of peoples' voices, music, or other sounds, and broadcasts the amplified sound through one or more electronic speaker devices, to an audience or persons attending the event or activity. For example, one or more hosts or attendees of such an event or activity may desire to access the PA system (as a speaker) to speak, give lectures, add comments, ask or answer questions, or the like. A microphone may be passed or delivered to that host or attendee, to allow the host or attendee to speak through the PA system. Passing and delivering of a microphone through an audience or group of attendees can be inconvenient, and can result in significant pauses between speakers of an audio program. To avoid the need to pass and deliver microphones through an audience, PCDs (such as, but not limited to, mobile phones) may be implemented to interface with the PA system in a manner such that one or more selected PCDs may act as a microphone for the PA system. Given the popularity of PCDs in modern society, hosts or attendees of an event or activity may likely carry their own PCDs. By configuring such PCDs and the PA system to interface, the hosts or attendees may employ their own PCDs as a microphone for the PA system.
However, when using a PCD as a microphone in a PA system, feedback (also known as howling) can occur when a sound that has been captured, amplified, and broadcasted by the PA system is recaptured by the microphone of the PCD and amplified/broadcasted again. In this manner, a loop is created such that the sound is continuously being re-amplified over a short period of time. Such loops produce, with the speakers of the PA system, a high-pitched (howling) sound that can be very unpleasant to the audience or attendees. PCDs with sensitive microphones can tend to create feedback when used as microphones to the PA systems.
Moreover, feedback can be more likely to occur, if audio signals (from multiple PCDs) having different amplitude ranges are fed into the input of the PA system. Conventional PA systems configured to suppress feedback for a first amplitude range, may not be capable of suppressing feedback for a second amplitude range which is greater than the first amplitude range. Thus, the conventional PA systems may not support feedback suppression for PCDs that output audio signals to the PA systems at different amplitude ranges.
One factor contributing to audio signals having different amplitude ranges is that PCDs may include hardware (such as, but not limited to, microphones) with different performance characteristics. This is at least partially because the various PCDs carried by audience members or attendees of an event or activity may be made by different manufacturers, may be different models from the same manufacturer, or may contain hardware from different component suppliers, such that the hardware may have different performance characteristics.
Another factor is that the speaking habits of different PCD users tend to be different from each other. For example, some users may speak loudly (or keep the PCD close) while other users may speak softly (or keep PCD far). Yet another factor is that different electronic speaker devices in a PA system may have different performance characteristics related to outputting sound. Some other factors include, but are not limited to, the speaking user's (speaker's) distance from the electronic speaker devices, the PCD microphone's frequency response, the sensitivity of the PCD microphone, the direction of the PCD microphone relative to the user, the acoustics of the room or area in which the PA system broadcasts, the direction of the electronic speaker devices with respect to speaking user's (speaker's) location, and/or the like.